1. Field of the Invention
The present invention relates to a measuring device, and more particularly to a pivotal measuring wheel.
2. Description of Related Art
With reference to FIGS. 7 and 8, a conventional measuring wheel includes a handle and a controller connecting to the handle. A first rod 90 has two ends respectively connected to the handle and pivotally connected to a second rod 91. The second rod 91 is rotatably connected to a wheel. Two cables 92 extend from the controller to the second rod 91 via the first rod 90 for measuring a rotational displacement of the wheel. The first rod 90 has two receiving slots 93 defined in the end of the first rod 90, which is connected to the second rod 91. The second rod 91 has two loading slots 94 defined in the end of the second rod 91, which is connected to the first rod 90. The two receiving slots 93 respectively communicate with the two loading slots 94. The two cables 92 are received in the two receiving slots 93 and the two loading slots 94 to prevent the cables 92 from being cut, such that the first rod 90 is pivotable relative to the second rod 91. However, the cables 92 are exposed on the first rod and the second rod and are easily stained by the environmental moisture such that the cables may not work properly.
Another conventional measuring wheel changes a connection between the first rod and the second rod, such that the first rod is sleeved on the second rod. The first rod is telescopically moved relative to the second rod for storage and easy carrying. However, the cables in the first rod and the second rod cannot be telescopically retracted and are folded in the first rod and the second rod. The cables are easily inserted between the first rod and the second rod and are easily worn and broken.
To overcome the shortcomings, the present invention tends to provide a measuring wheel to mitigate or obviate the aforementioned problems.